Synthesize derivatives of gossypol and test them for antifertility effects and for toxicity in rats. Prepare 5 gm quantities of 14 target compounds, of which 12 would be made in the first year of the contract. The proposed structures include the hexamethyl ether and hexamethyl acetate and diethers of gossypol; derivatives in which the aldehydic group is removed or reduced; derivatives in which dianilino Schiff bases are prepared of the carbonyl group; lactones prepared by oxidation of the carboxyl group; the cyclic ether prepared by reduction of the lactone; nathaquinone derivatives prepared by oxidation of gossypol; didesoxy gossypoles in which the hydroxyl group in position 1 has been removed; and hemigossypol prepared by complete synthesis. The research plan also includes provision for isolation of the needed quantities of gossypol for use as an intermediate in the synthetic program.